This invention relates to a vibration-isolation mounting apparatus and more particularly to a mounting apparatus for mounting a cab structure to the frame of a construction machine.
Typically, in construction machines it is common for the cab structure to include an operator station and a roll over protection structure (ROPS) in one integrated structure. Since such machines are typically operated across rough terrain, a vibration-isolation type structure is oftentimes used to mount the cab structure the frame members of the construction machine. Such vibration-isolation type structures typically consist of compressed rubber or other elastomeric type materials which are positioned between the cab structure and the frame members and are secured in place by a threaded fastener. Being resiliently mounted as such, the cab structure is permitted to move a preselected amount with respect to the vehicle""s frame.
A problem which may arise is that the vehicle""s roll over protection structure is intended to remain attached to the frame in the event of vehicle rollover, collision, or other violent event and the vibration-isolation type mounting points may comprise a weak link, particularly if worn or not properly maintained, in the chain of afforded protection do the aforementioned flexible nature of these types of joints and the fact the a large proportion of the generated forces caused by the movement of the cab relative to the frame are borne by aforementioned bolt or bolts. Some typical methods to compensate for bolt failure include adding additional bolted joints, adding one or more shear pins, or providing each bolt with a bolstering-type structure such as rigid sleeves placed concentrically about the bolt. Examples of sleeve-type arrangements can be found in the prior art U.S. Pat. Nos. 5,110,081 and 4,515,234 issued to, respectively, Lang, Jr. and Loy et al., as well as the prior art European Patent No. EP-429-084 issued to Komp et al. While these arrangements may be adequate, the bolt remains the primary load bearing structure for maintaining attachment of the ROPS to the vehicle frame.
In one aspect of the present invention, a mounting apparatus is adopted for mounting a cab structure to a frame member. The mounting apparatus includes first resilient member positioned between the cab structure and the frame member and maintains the cab structure and the frame member in spaced relation to one another. A mounting structure is provided for maintaining the first resilient member between the cab structure and the frame member.
In another aspect of the present invention, a method of rotating a cab structure relative to a frame member is provided. The method includes the first step of providing a first mounting apparatus which includes a resilient member positioned between the cab structure and the frame member, and a mounting structure used for maintaining the resilient member between the cab structure and the frame member. The mounting structure has an aperture in its upper portion that is sized to receive a first pin. The pin, in turn, has a longitudinal first mounting pin axis. The next step consists of rotating the cab structure about the longitudinal first pin axis.